What is color ?

This is one of the most daunting question that poses itself on someone who wants to delve into the science of color. Color is something that is so integral to our lives and the world around us yet it is very difficult to come to a conclusive answer to this question.

While at Adobe I was doing this excersice on Color Management and this question popped up from somewhere and we went about dissecting the matter at hand.

The first thing the need to be realized is the world around us is colorless. There is no color in the universe !!. How cool is that ;-) ?? Its all energy floating around in space. When this energy falls on the cones in the retina it creates a sensation we call COLOR. It exists only in our consciousness, outside which color has no meaning.

Is the shirt your are wearing blue? Are the leaves green? Well there IS no color in the outside world. So you can take your elementry school book that thought you about color and dumb it in the trash. (Well not exactly, they do teach you some really great things like the 3 laws of motion :D ) When they show light falling on a red object and red light coming out of it, it actually dosent happen that ways.

What happens?
The physics:
When light falls on an object its electrons gets excited and move to a higher energy level. When they come back to their ground ( 0 energy ) state they release energy. A lot of this energy is lost until its a true reflector of light. This energy is emitted as photons and photons are the indivisible constituens of any kind of energy, here light energy. The energy emitted determines the wavelength of the light and hence the color response it might elicit in the brain.

The Biology:
Our eyes has receptors called cones that perceive color. There are 3 kinds of them, Reb, Blue and Green. Why these names? Because they respond to light wavelengths in the corresponding wavelengths. When the photons hit the retina in our eyes they activate these cones depending in the wavelength they are in. Lets say a yellow colored (pardon my usage) light would activate the red and the green cones. When the inputs from the red and the green cones are combined higher up in the neural pathway the color we SEE is yellow.

The Metaphysics:
The realization that the seen object is Yellow in color happen in the brain. The colors in the brain are arranged in a somewhat circular manner which was first discovered by Munzel a french painter. He showed that color existed in a circular pattern quite unlike the linear VIBGYOR that we have come to accept. There was a range of colors filling up the gap between Violet and Red which are called transedental colors. These colors do not exist in the light spectrum. Newton was working on something similar after he discovered diffraction, but somehow he gave up this quest of his (more on this sometime later).

So next time you look around yourself just pause for a moment and think... Color ??? Its all in the mind, i say :))